The plastic molding industry has long been confronted with the problem of how to efficiently separate molded parts from runners as these components are discharged from a molding machine. This problem is particularly severe where large quantities of small parts are being simultaneously molded during each operation. To improve on this separation operation, there has been developed a "fingered" separator which employs a movable support or base, such as a belt, having a plurality of fingers projecting outwardly therefrom. The mixture of components is deposited on the fingered support such that the parts, being of smaller size, fall downwardly between the fingers for collection at a selected location. The runners, being of greater length, are caught by the fingers and are thus moved to a different location for collection. Such fingered separators are now well known and are rather extensively utilized in the plastic molding industry. One highly desirable type of fingered separator, wherein the fingered belt is supported on three rollers, is disclosed in U.S. Pat. No. 3,789,981 as owned by the assignee of this application.
To further improve upon the overall separating operation, fingered separators have been incorporated into a conveying and separating apparatus, which apparatus includes a conveyor (often a belt conveyor) for transporting the mixture of parts and runners to the fingered separator. This belt conveyor conventionally has the upper reach thereof inclined upwardly at a substantial angle, such that the mixture of components is deposited on the upper reach adjacent the lower end, with the mixture of components then being conveyed upwardly so as to be discharged onto the fingered separator. Because of the incline of the upper belt reach, coupled with the smallness and light weight of the parts, the belt is conventionally provided with upstanding transverse lugs to permit the components to be efficiently and effectively transported upwardly to the separator. Such conveyor, as illustrated by U.S. Pat. Nos. 4,171,044 and 4,050,575 both owned by the assignee of this application, are typically utilized in conjunction with a fingered belt separator positioned adjacent the upper conveyor belt roller so that there is a selected gap defined between the upper conveyor belt roller and an upwardly-moving inclined reach of the fingered separator belt. The conveyor thus deposits the mixture of components into this gap, whereupon the small molded parts fall downwardly between the fingers and are collected, whereas the runners are caught by the fingers and moved upwardly therewith and are hence transported by the fingered separator belt for discharge at a different location.
This known conveyor-separator apparatus has been proven to operate in a highly desirable and efficient manner for effecting separation of parts and runners at a relatively high rate of speed, and is able to achieve this separation with a high degree of efficiency. This known conveyor-separator apparatus has also proven highly desirable since, even though the conveyor and separator portions are formed as separable units which are joined together, nevertheless the separator unit is slave driven from the conveyor unit so that only a single drive motor is required, in contrast to other known conveyor-separator apparatus which have required separate drive motors for both units. In addition, the use of a three-roller support for the fingered separator belt is also believed to provide more efficient separation of the parts and runners than is achieved by other competitive apparatus which utilize only a two-roller support for the fingered separator belt.
Thus, while the assignee's conveyor-separator apparatus has performed in a highly desirable manner and hence has achieved substantial commercial acceptance, it still possesses structural and operational limitations which are less than optimum, particularly since the separation gap is of a fixed width, and changing the width of this gap has previously been possible only by rather extensive reconstruction of the apparatus, such as by positioning spacers between the adjoining ends of the conveyor and separator units, and by additionally removing and replacing the drive gears which join between the conveyor and separator units so as to compensate for the additional spacers. Needless to say, such a modification is time-consuming and requires substantial disassembly and reassembly of both units, which not only requires substantial service time but also results in the apparatus being shut down and hence nonproductive for a substantial period of time.
Since many industries are now molding substantially larger parts and hence larger runners, the separation gap required for effectively separating these larger parts and runners is substantially greater than the separation gap required for separating small molded parts, and this large separation gap can not be successfully utilized with small parts. Hence, the present invention effectively overcomes this disadvantage by enabling the separation gap to be easily and selectively adjusted over a substantial range so that the apparatus can be efficiently and successfully utilized for separating molded mixtures of components which may be of either small or large size. This adjustment can be accomplished without requiring any reconstruction or disassembly of the apparatus, and in fact can be accomplished in a simple and efficient manner requiring very little time or effort. At the same time, this desirable apparatus still permits the separating unit to be slave driven from the conveying unit, but does not require any replacement of the drive train used for drivingly connecting the two units together.
In the improved conveyor-separator apparatus of this invention, the separator unit is slave driven from the conveyor unit by a gear train which employs an idler gear rotatably supported on the separator unit, which idler gear projects from the housing of the separator unit so as to be disposed in meshing engagement with a suitable gear associated with the conveyor unit when the two units are joined together. This gear train also employs a drive gear which is in meshing engagement with the idler gear and is coaxially secured relative to the separator belt roller disposed adjacent the lower end of the gap. This driven gear is supported on an arm which is swingable about the axis of the idler gear, which arm can be selectively secured in a desired location. This swinging of the arm causes the axis of the drive gear, and hence the axis of the aforesaid separator belt roller, to be selectively moved toward or away from the conveyor unit so as to selectively vary the width of the separation gap.
Other objects and purposes of the invention will be apparent to persons familiar with apparatus of this general type upon reading the following specification and inspecting the accompanying drawings.